I did know about all packages being in 'all', just gave 'www' as an example. My question really is: Why are there hardly any packages for i386? Is this normal, i.e. early in the release cycle. Where can I read about that?

On searching a few repository mirrors for packages, it seems that there are only a limited number available for NetBSD 7.0 i386. e.g.

My understanding is thatftp://nyftp.netbsd.org
is designated to build amd64 and i386 binary packages. The other repositories mirror that build site.

The NetBSD structure is markedly different than OpenBSD or FreeBSD where binary packages are available at the same time as the release. In the case of the recent 5.8 OpenBSD release, packages appeared on the servers before the core distribution.

This is in part due to the massive task of trying build binaries for all the different architectures and not having the resources to produce timely builds. The limited number of available i386 binary packages are those that built on the first pass. The others were missing a dependency and did not build on the first build cycle. Correcting the build scripts occurs incrementally and often requires multiple builds. For this reason, you are more likely to get a complete system if your use slightly older binaries, ie Q2 as opposed to the newly released Q3. Since NetBSD 7.0 is a new release, there are no prior builds for i386. AMD64 binaries were mostly compiled using a Release Candidate core.